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TestUpdateHysteresis
Exact test identity: go.temporal.io/server/common/number/TestCompact8Suite/TestUpdateHysteresis
- Package
go.temporal.io/server/common/number- Suite / test hierarchy
TestCompact8Suite/TestUpdateHysteresis- Test
TestUpdateHysteresis- Introduced at
- compact8.go ×1 Frontier kind: Joint frontier
- Covered ranges
- 13
- Covered lines
- 42
- Covered files
- 1
Covered source
Expand a file to inspect source; the > gutter marks covered lines.
go.temporal.io/server/common/number/compact8.go 42 covered LOC · 13 ranges
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// DecodeCompact8 converts a Compact8 value to an int64.
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func DecodeCompact8(b Compact8) int64 {
compact8.go
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if b == 0 {
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return 0
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}
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m := int(b % 12)
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if e == 0 {
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return int64(m) << (compact8offset + 1)
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}
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return int64(12+m) << (e + compact8offset)
compact8.go
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}
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// The value is rounded down to the nearest representable value.
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// Negative values go to 0 and values above the maximum representable go to 255.
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func EncodeCompact8(value int64) Compact8 {
compact8.go
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if value <= 0 {
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return 0
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}
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bitLen := bits.Len64(uval)
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// Find shift such that uval >> shift is in [12, 23].
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// This extracts the significand for the normalized representation.
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shift := max(bitLen-5, 0)
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sig := int(uval >> uint(shift))
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if sig >= 24 {
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shift++
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sig = int(uval >> uint(shift))
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}
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>
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if e >= 1 {
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b := e*12 + m
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if b > 255 {
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return 255
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}
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}
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// it sticks to prev unless the new code is significantly closer. This prevents
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// oscillation when the underlying value fluctuates near a bucket boundary.
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func UpdateCompact8(value int64, prev Compact8) Compact8 {
compact8.go
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newCode := EncodeCompact8(value)
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if newCode == prev {
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}
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newDist := value - DecodeCompact8(newCode) // always >= 0 (round-down)
compact8.go
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oldDist := DecodeCompact8(prev) - value
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if oldDist < 0 {
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oldDist = -oldDist
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}
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// Require the new code to be closer by at least half a bucket width
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// (at the smaller of the two exponent levels). This shifts the
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// transition point from the midpoint to the 3/4 mark of the gap,
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// creating a dead zone that prevents chatter.
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e := max(1, min(int(prev/12), int(newCode/12)))
compact8.go
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margin := int64(1) << (e + compact8offset - 1)
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if newDist < oldDist-margin {
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return newCode
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}
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}